The instructions in the video were specific to 11.10 - both Unity and its components have moved significantly forward in 12.04. You will not be able to use the video instructions to move the launcher in 12.04.

The only solution (currently) - is to install 11.10 and use the PPA. If (or when?) the PPA is updated, then you can upgrade to 12.04.

Specifically to the error you are seeing - unless a typo in your question - this should be: